The present invention relates to locking devices of the type which utilize a lock cylinder containing a lock plug that is rotatable by rotation of a key inserted in the lock cylinder, a threaded rod being connected to the lock plug in a manner such that the threaded rod rotates with rotation of the lock plug. More particularly, the present invention is directed to locking device constructions which increase the applications to which such lock plugs can be utilized as well as improvements in particular locking device arrangements.
Locking devices of the above mentioned type are known. For example, the Chicago Lock Company "Chicago Ace Stud Lock" series CH-4107 is a housingless stud lock which is retained on a wall by a nut threaded thereon. Such locks are conventionally utilized for drawing doors and covers down tight on coin meters, vending machines and the like. However, such have not been utilized in a padlock-type environment.
U.S. Pat. No. 3,600,912 shows a screw-type lock assembly for locking sliding members. In the arrangement according to this patent, a removable lock plug is received within a cylindrical lock housing, which lock housing is passed through the sliding member and a wall frame member so as to prevent shifting of the sliding member. In the assembled position, the housing engages a threaded plate permanently attached to an internal wall frame portion and is held against relative rotation with respect thereto. A threaded rod associated with the lock tumblers can then be threaded into engagement with the threads of the plate by rotation of the key so as to secure the assembly in place. Such an arrangement is not utilizable as a padlock in conjunction with hasps, and since it has multiple parts which are not fastened together in an unlocked position of the assembly, the lock can be rendered useless by a loss of one of the parts. Furthermore, no arrangement for weather proofing the locking assembly is provided. In another known application of screw-type locks according to U.S. Pat. No. 2,565,659, a speedometer cable fitting lock utilizes a key operated, tumbler equipped screw plug for securing a pair of semi-annular shackle members together. However, since the shackle halves must be pivotally brought into engagement with each other, and since threaded engagement of the locking plug threads with threads in one of the shackle members can only occur when the two are in axial alignment with each other, the locking plug is a removable member that is not connected to a lock housing of the shackle in an unlocked condition so that the semi-annular members can be closed about a cable, the plug inserted through one of the shackle members and progressively threaded down into the other of the shackle members. Such an arrangement is both cumbersome to use and subject to being rendered useless due to a misplacing of the locking plug. Furthermore, no provisions are made for weatherproofing the locking plug.
Accordingly, it is an object of the present invention to provide improved padlock and shackle-type locking arrangements utilizing locking devices of the initially mentioned type.
It is a further object to achieve such improved screw-type locks wherein the lock cylinder can be securely retained within a protective housing in a manner that eliminates any requirement for the lock cylinder to be detatchable therefrom in use.
It is yet another object in accordance with the present invention to provide locks of the previously described type which are weatherproof for outdoor uses.
Still a further object of the present invention is to achieve locks of the screw-type that are constructed in a manner that avoids part of the lock assembly from becoming lost due to inadvertent detatchment.
The above noted objects are achieved in accordance with a first embodiment of the invention designed for padlock-type applications by the provision of a relatively massive cylindrical lock housing within which a lock cylinder is fastened against rotational and axial movements relative to the lock housing, and from which a screw threaded rod (that is connected with the tumbler equipped, lock plug so as to rotate with rotation of the lock plug by a key) extends, and a relatively massive cylindrical sleeve member having a blind bore therein, a portion of which is threaded for engagingly receiving the threaded rod. Relative rotation between the lock housing and the sleeve member is achieved, in one embodiment, by a counter bore construction on the sleeve member of non-circular cross section being engageable with a male portion of the lock housing that is also of a non-circular transverse cross section. This male portion of the lock housing is greater in length than the depth of the counter bore so as to enable a hasp to be secured thereon between the lock housing and sleeve member.
In accordance with a second embodiment, particularly suited for trailer theft prevention applications, relative rotation between the lock housing and sleeve member is achieved by a shackle that is formed of a pair of semi-annular members to which the lock housing and sleeve member are tangentially permanently fastened at a respective end of each. Fastening of the screw thread rod into the sleeve member (without the lock cylinder being removable and despite the fact closing of the shackle members requires a pivotal swinging movement) is facilitated by constructing the threaded portion of the blind bore as a threaded sleeve member that is displaceably received and retained within the blind bore.
In both embodiments, the lock cylinder is rendered weather proof by a cover cap assembly that is provided with a resilient, externally threaded sleeve mounted upon the exterior of the lock housing and a cover cap retainable upon the threaded sleeve. The cap and threaded sleeve are interconnected by a flexible coupling such as a chain. Still further, the sleeve can be utilized to hide the fastening means securing the lock plug within the lock housing.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.